1. Field of the Invention
The present invention relates to a reaction device incorporating a carbon monoxide remover to remove carbon monoxide by oxidizing it and a vaporizer to vaporize fuel and water, and relates to an electronic device.
2. Description of Related Art
In recent years, a fuel cell has attracted attention as a clean power source having high energy conversion efficiency, and it has been developed to put the fuel cell to practical use, such as a fuel cell powered vehicle and electric home. The fuel cell is a device to generate electrical energy by an electrochemical reaction of hydrogen and oxygen, and a reaction device to generate hydrogen from a mixture gas of a fuel and water is connected to such fuel cell. For example, a reaction device (30) described in Japanese Patent Application Laid-Open Publication No. 2001-118595 includes combustors (50) and (51) each mounted in a ring shape, a vaporizer (35) installed above the combustors (50) and (51), reformers (21) and (32) provided in a scroll pattern above the vaporizer (35), and a carbon monoxide remover (34) communicating with the ends of the reformers (21) and (32) on their peripheral sides. In the reaction device, a heated gas heated by the combustors (50) and (51) flows while touching the outer side of the vaporizer (35) to heat the vaporizer (35). After that, the heated gas flows in a scroll pattern along the reformers (21) and (32) while touching the outer sides of the reformers (21) and (32) to heat the reformers (21) and (32). In the heated vaporizer (35), the fuel and the water are vaporized by being heated, and the mixture gas of the vaporized fuel and water is sent to the reformers (21) and (32). In the reformers (21) and (32), a hydrogen gas, a carbon monoxide gas, and the like, are generated from the fuel and the water, and the generated gases are sent from the reformers (21) and (32) to the carbon monoxide remover (34) In the carbon monoxide remover (34), carbon monoxide is removed by being oxidized. The hydrogen gas obtained by such a way is sent to the fuel cell, and electrical energy can be obtained in the fuel cell.
On the other hand, the research and development for mounting the fuel cell as a power source have been made also in a cellular phone, a notebook-sized personal computer, and the like, which have been being miniaturized and enhanced in their properties. If the fuel cell is mounted in a small-sized device, such as the cellular phone and the notebook-sized personal computer, not only the fuel cell but also the reaction device must be miniaturized. As a technique to miniaturize the reaction device, for example, there is a technique described in Japanese Patent Application Laid-Open Publication No. 2005-132712, where the reaction device (1) is formed by stacking a carbon monoxide remover (2c), a reformer (2b), and a vaporizer (2a) from the bottom in order. Any of the carbon monoxide remover (2c), the reformer (2b), and the vaporizer (2a) has a flow path formed by joining two substrates on each of which a groove to be the flow path is formed. Moreover, a heating element, which heats by electricity, is provided to each of the carbon monoxide remover (2c), the reformer (2b), and the vaporizer (2a). Moreover, a vacant space is formed between each of the carbon monoxide remover (2c), the reformer (2b), and the vaporizer (2a), which thereby enables to set them at optimum temperatures individually.
However, in the reaction device (30) described in the Japanese Patent Application Laid-Open Publication No. 2001-118595, the heat generated by the combustors (50) and (51) is transferred to the vaporizer (35) and the reformers (21) and (32) through the medium of the gas, and the heated gas is ejected after the gas further has heated the vaporizer (35) and the reformers (21) and (32). Consequently, heat use efficiency is bad.
Moreover, in the reaction device (1) described in the Japanese Patent Application Laid-Open Publication No. 2005-132712, the reformer (2b), the carbon monoxide remover (2c), and the vaporizer (2a) are separately heated, and no heat conduction is caused among the reformer (2b), the carbon monoxide remover (2c), and the vaporizer (2a) owing to the vacant spaces formed among them. Consequently, the heat use efficiency is bad.